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Experiment and Analysis Code for the study "Mind the Machines: Applying Implicit Measures of Mind Perception to Social Robotics"

Plant brassinosteroid hormones (BRs) regulate growth in part through altering the properties of the cell wall, the extracellular matrix of plant cells. Conversely, feedback signalling from the wall connects the state of cell wall homeostasis to the BR receptor complex and modulates BR activity. Here, we report that both pectin-triggered cell wall signalling and impaired BR signalling result in altered cell wall orientation in the Arabidopsis root meristem. Furthermore, both depletion of endogenous BRs and exogenous supply of BRs triggered these defects. Cell wall signalling-induced alterations in the orientation of newly placed walls appear to occur late during cytokinesis, after initial positioning of the cortical division zone. Tissue-specific perturbations of BR signalling revealed that the cellular malfunction is unrelated to previously described whole organ growth defects. Thus, tissue type separates the pleiotropic effects of cell wall/BR signals and highlights their importance during cell wall placement., Summary: Both increased and reduced BR signalling strength results in altered cell wall orientation in the Arabidopsis root, uncoupled from whole-root growth control.

Microbial contamination caused by bacterial adhesion and colonization onto the materials surfaces has long been a serious threat to human health. Thus, it is imperative to develop advanced antimicrobial materials for bio-applications. Here, a unique polydopamine/ hydroxyapatite/nisin (PDA/HAP/Nisin) composite with good bioactivities and enhanced antibacterial activities have been developed. The uniform PDA particles are first prepared via the dopamine self-polymerization in an alkaline water-ethanol mixed solvent. Due to the abundance surface catecholamine moieties, PDA particles can serve as the powerful templates for the in-situ mineralization of hydroxyapatite (HAP) in a simulated body fluid (SBF) solution, forming PDA/HAP composites. Transmission electron microscopy, scanning electron microscopy, transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction are used to investigate the morphology, surface composition, and crystalline structure of the PDA/HAP composites. These PDA/HAP composites are utilized as the reservoir for loading the antimicrobial peptide–nisin. Ultraviolet visible spectrophotometry analysis shows that PDA/HAP composites have exhibited a high loading capacity and a superior loading efficiency for nisin. The resulting PDA/HAP/Nisin composites are ideal antimicrobial biomaterials for bio-application because they exhibit not only a significant in vitro cytocompatibility to human embryonic kidney HEK293 T cells, but also the enhanced antibacterial activities against Staphylococcus aureus (Gram-positive bacteria). These advantageous properties of the PDA/HAP/Nisin composites allow them as the promising candidates for a broad range of bio-applications, e.g., drug delivery, implant engineering, and bio-scaffold.

This study investigated the effect of protein content on the physicochemical and rheological properties of waxy rice flour and textural properties of glutinous dumplings. Mechanical removal of protein content significantly influenced the color parameters and slurry transparency of waxy rice flour, thereby resulting in a brighter and less yellow color with decreased protein content. Swelling power and solubility increased as a result of decreased thiol groups, and weakened starch-protein network interactions, thereby resulting in increasing cooking solid losses and decreasing height to diameter ratios of cooked glutinous dumplings. The pasting properties revealed that the viscosities of the peak, trough, final, and after breakdown values increased with decreasing protein content. Mechanical property determinations using dynamic rheometer and texture analyzers indicated a less elastic gel-like network structure with decreased protein content of waxy rice flour and glutinous dumplings. This study indicated that partial removal of protein from waxy rice flour may lead to potential energy savings and could be helpful in food processes. Among varieties ranked for personal preference by tasters, glutinous dumplings with 3% protein content were the most preferred, with a white and glossy appearance, a less chewy texture, and a sticky feeling in the mouth.

This paper proposes a 6 bit floating window asynchronous level crossing ADC in 180nm CMOS technology for applications with sparse input signals. Two different hysteresis comparators are used to detect the rise and fall of the input signals respectively. The hysteresis width can changing with the change speed of input signal, so that the level crossing ADC can not only reduce the collection of invalid data when the signal changes slowly, but also collect the peak signal when the signal changes rapidly. Operating under a supply voltage of 1.8 V, the ADC consumes 31.8–41.5 μnW from 1 Hz to 50 kHz.

Impact of covalent and non-covalent binding interactions on physicochemical, structural, and rheological properties of waxy rice flour were investigated using several typical types of chemicals. Dynamic rheometer was used to investigate the viscoelastic properties and resistance to deformation or shearing. Both hydrogen bonds and hydrophobic interactions were necessary for waxy rice flour to form a material with stable structure matrix. Besides this, X-ray diffraction pattern and pasting property measurements showed that the relative crystallinity and pasting viscosity values of waxy rice flour exposed to SDS and l-cysteine treatments increased whereas those of urea decreased compared with the control. Addition of acid, alkali, and NaCl might result in electrostatic forces, ion interactions, and indirectly change hydrogen bonds and hydrophobic interactions between starch and protein, which played a synthetic role on property changes of waxy rice flour.

The cell wall is a defining feature of plant cells. It is a rigid, yet flexible, layer surrounding each cell outside the plasma membrane and is mainly composed of polysaccharides such as cellulose, hemicellulose, and pectin, as well asm to a lesser extent, phenolic compounds such as lignin and structural proteins. Plant cell wall is central to nearly all aspects of plant. Its biosynthesis and remodeling are essential for cell division, expansion and differentiation, the fundamental events through plant growth and development. In brief, cell walls shape the cells, which is crucial for organ formation, provide mechanical support to the plant, control cell-to-cell adhesion, form the interface between cells, which is indispensable for cellular communication, and regulate plant-pathogen/environment interactions. As plants permanently face intrinsic and extrinsic cues from developmental programs and the environment, this information must be correctly conveyed into the cells in order to adjust the plant’s growth behavior and reallocate the resources accordingly. Therefore, a cell wall surveillance and signalling system must exist to ensure transmission of the information. Roots form the hidden half of the plant and perform numerous physical and physiological functions such as anchoring, nutrient uptake and transport. The primary root of the model organism in plant research, Arabidopsis thaliana, is formed with different tissues organized as longitudinal cell files that are radially patterned in a concentric manner, which provides an easily accessible model to study plant development. By using this model, previous studies in our lab have revealed the plasma membrane residing RECEPTOR LIKE PROTEIN (RLP)44 as key factor for cell wall surveillance and signalling. RLP44 monitors pectin status in the cell wall and transduces the signal of changes in cell wall integrity through interaction with the brassinosteroid receptor BRI1, which in turn activates a well-described signalling cascade to regulate plant growth transcriptionally. As in plants, different tissues fulfill distinct biological functions and have similar, yet distinguishable, characteristics in their cell walls, investigation of RLP44-mediated cell wall signalling in tissue-specific context would bring more insights into how plants co-ordinates its growth and development in responses to cell wall changes at tissue level. To do so, we made use of the recently developed GreenGate cloning technique and the dexamethasone-inducible system pOp6/GR-LhG4. By using promoters driving expression specifically in different cell types/ tissues, we ectopically expressed pectin-modifying gene PECTIN METHYLESTERASE INHIBITOR 5 (PMEI5) and studied the responses of the plant to the loss of cell wall integrity. Here, we showed that cell wall homeostasis had pronounced impact on root growth, especially on in root morphogenesis, meristem size control, division plane determination through CDS maintenance, and tissue patterning. This influence was manifested as varying phenotypes at tissue level, implemented probably through crosstalks between brassinosteroid and other hormone signalling pathways in both cell-autonomous and non cell-autonomous manner. Besides, the previously described RLP44-mediated cell wall signalling exerts its role in a cell type/tissue-specific way and other cell wall sensing and signalling mechanisms are also possibly involved in the responses to cell wall perturbation. However, biochemical and histological characterization of cell wall properties as well as genetic studies for discovering the underlying molecular mechanisms will be necessary to further understand the role of cell identity in cell wall signalling and plant growth regulation.

Maize (Zea mays) is an important C4 plant due to its widespread use as a cereal and energy crop. A second-generation genome-scale metabolic model for the maize leaf was created to capture C4 carbon fixation and investigate nitrogen (N) assimilation by modeling the interactions between the bundle sheath and mesophyll cells. The model contains gene-protein-reaction relationships, elemental and charge-balanced reactions, and incorporates experimental evidence pertaining to the biomass composition, compartmentalization, and flux constraints. Condition-specific biomass descriptions were introduced that account for amino acids, fatty acids, soluble sugars, proteins, chlorophyll, lignocellulose, and nucleic acids as experimentally measured biomass constituents. Compartmentalization of the model is based on proteomic/transcriptomic data and literature evidence. With the incorporation of information from the MetaCrop and MaizeCyc databases, this updated model spans 5,824 genes, 8,525 reactions, and 9,153 metabolites, an increase of approximately 4 times the size of the earlier iRS1563 model. Transcriptomic and proteomic data have also been used to introduce regulatory constraints in the model to simulate an N-limited condition and mutants deficient in glutamine synthetase, gln1-3 and gln1-4. Model-predicted results achieved 90% accuracy when comparing the wild type grown under an N-complete condition with the wild type grown under an N-deficient condition.